--- /dev/null
+/*
+ * Crypto user configuration API.
+ *
+ * Copyright (C) 2011 secunet Security Networks AG
+ * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/cryptouser.h>
+#include <linux/sched.h>
+#include <net/netlink.h>
+#include <linux/security.h>
+#include <net/net_namespace.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/skcipher.h>
+
+#include "internal.h"
+
+#define null_terminated(x) (strnlen(x, sizeof(x)) < sizeof(x))
+
+static DEFINE_MUTEX(crypto_cfg_mutex);
+
+/* The crypto netlink socket */
+static struct sock *crypto_nlsk;
+
+struct crypto_dump_info {
+ struct sk_buff *in_skb;
+ struct sk_buff *out_skb;
+ u32 nlmsg_seq;
+ u16 nlmsg_flags;
+};
+
+static struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact)
+{
+ struct crypto_alg *q, *alg = NULL;
+
+ down_read(&crypto_alg_sem);
+
+ list_for_each_entry(q, &crypto_alg_list, cra_list) {
+ int match = 0;
+
+ if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
+ continue;
+
+ if (strlen(p->cru_driver_name))
+ match = !strcmp(q->cra_driver_name,
+ p->cru_driver_name);
+ else if (!exact)
+ match = !strcmp(q->cra_name, p->cru_name);
+
+ if (!match)
+ continue;
+
+ if (unlikely(!crypto_mod_get(q)))
+ continue;
+
+ alg = q;
+ break;
+ }
+
+ up_read(&crypto_alg_sem);
+
+ return alg;
+}
+
+static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_cipher rcipher;
+
+ strncpy(rcipher.type, "cipher", sizeof(rcipher.type));
+
+ rcipher.blocksize = alg->cra_blocksize;
+ rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
+ rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
+
+ if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
+ sizeof(struct crypto_report_cipher), &rcipher))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_comp rcomp;
+
+ strncpy(rcomp.type, "compression", sizeof(rcomp.type));
+ if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
+ sizeof(struct crypto_report_comp), &rcomp))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static int crypto_report_one(struct crypto_alg *alg,
+ struct crypto_user_alg *ualg, struct sk_buff *skb)
+{
+ strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
+ strncpy(ualg->cru_driver_name, alg->cra_driver_name,
+ sizeof(ualg->cru_driver_name));
+ strncpy(ualg->cru_module_name, module_name(alg->cra_module),
+ sizeof(ualg->cru_module_name));
+
+ ualg->cru_type = 0;
+ ualg->cru_mask = 0;
+ ualg->cru_flags = alg->cra_flags;
+ ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
+
+ if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
+ goto nla_put_failure;
+ if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
+ struct crypto_report_larval rl;
+
+ strncpy(rl.type, "larval", sizeof(rl.type));
+ if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
+ sizeof(struct crypto_report_larval), &rl))
+ goto nla_put_failure;
+ goto out;
+ }
+
+ if (alg->cra_type && alg->cra_type->report) {
+ if (alg->cra_type->report(skb, alg))
+ goto nla_put_failure;
+
+ goto out;
+ }
+
+ switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) {
+ case CRYPTO_ALG_TYPE_CIPHER:
+ if (crypto_report_cipher(skb, alg))
+ goto nla_put_failure;
+
+ break;
+ case CRYPTO_ALG_TYPE_COMPRESS:
+ if (crypto_report_comp(skb, alg))
+ goto nla_put_failure;
+
+ break;
+ }
+
+out:
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static int crypto_report_alg(struct crypto_alg *alg,
+ struct crypto_dump_info *info)
+{
+ struct sk_buff *in_skb = info->in_skb;
+ struct sk_buff *skb = info->out_skb;
+ struct nlmsghdr *nlh;
+ struct crypto_user_alg *ualg;
+ int err = 0;
+
+ nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
+ CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
+ if (!nlh) {
+ err = -EMSGSIZE;
+ goto out;
+ }
+
+ ualg = nlmsg_data(nlh);
+
+ err = crypto_report_one(alg, ualg, skb);
+ if (err) {
+ nlmsg_cancel(skb, nlh);
+ goto out;
+ }
+
+ nlmsg_end(skb, nlh);
+
+out:
+ return err;
+}
+
+static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
+ struct nlattr **attrs)
+{
+ struct crypto_user_alg *p = nlmsg_data(in_nlh);
+ struct crypto_alg *alg;
+ struct sk_buff *skb;
+ struct crypto_dump_info info;
+ int err;
+
+ if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+ return -EINVAL;
+
+ alg = crypto_alg_match(p, 0);
+ if (!alg)
+ return -ENOENT;
+
+ err = -ENOMEM;
+ skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+ if (!skb)
+ goto drop_alg;
+
+ info.in_skb = in_skb;
+ info.out_skb = skb;
+ info.nlmsg_seq = in_nlh->nlmsg_seq;
+ info.nlmsg_flags = 0;
+
+ err = crypto_report_alg(alg, &info);
+
+drop_alg:
+ crypto_mod_put(alg);
+
+ if (err)
+ return err;
+
+ return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
+}
+
+static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct crypto_alg *alg;
+ struct crypto_dump_info info;
+ int err;
+
+ if (cb->args[0])
+ goto out;
+
+ cb->args[0] = 1;
+
+ info.in_skb = cb->skb;
+ info.out_skb = skb;
+ info.nlmsg_seq = cb->nlh->nlmsg_seq;
+ info.nlmsg_flags = NLM_F_MULTI;
+
+ list_for_each_entry(alg, &crypto_alg_list, cra_list) {
+ err = crypto_report_alg(alg, &info);
+ if (err)
+ goto out_err;
+ }
+
+out:
+ return skb->len;
+out_err:
+ return err;
+}
+
+static int crypto_dump_report_done(struct netlink_callback *cb)
+{
+ return 0;
+}
+
+static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct nlattr **attrs)
+{
+ struct crypto_alg *alg;
+ struct crypto_user_alg *p = nlmsg_data(nlh);
+ struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
+ LIST_HEAD(list);
+
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+ return -EINVAL;
+
+ if (priority && !strlen(p->cru_driver_name))
+ return -EINVAL;
+
+ alg = crypto_alg_match(p, 1);
+ if (!alg)
+ return -ENOENT;
+
+ down_write(&crypto_alg_sem);
+
+ crypto_remove_spawns(alg, &list, NULL);
+
+ if (priority)
+ alg->cra_priority = nla_get_u32(priority);
+
+ up_write(&crypto_alg_sem);
+
+ crypto_mod_put(alg);
+ crypto_remove_final(&list);
+
+ return 0;
+}
+
+static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct nlattr **attrs)
+{
+ struct crypto_alg *alg;
+ struct crypto_user_alg *p = nlmsg_data(nlh);
+ int err;
+
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+ return -EINVAL;
+
+ alg = crypto_alg_match(p, 1);
+ if (!alg)
+ return -ENOENT;
+
+ /* We can not unregister core algorithms such as aes-generic.
+ * We would loose the reference in the crypto_alg_list to this algorithm
+ * if we try to unregister. Unregistering such an algorithm without
+ * removing the module is not possible, so we restrict to crypto
+ * instances that are build from templates. */
+ err = -EINVAL;
+ if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
+ goto drop_alg;
+
+ err = -EBUSY;
+ if (atomic_read(&alg->cra_refcnt) > 2)
+ goto drop_alg;
+
+ err = crypto_unregister_instance((struct crypto_instance *)alg);
+
+drop_alg:
+ crypto_mod_put(alg);
+ return err;
+}
+
+static struct crypto_alg *crypto_user_skcipher_alg(const char *name, u32 type,
+ u32 mask)
+{
+ int err;
+ struct crypto_alg *alg;
+
+ type = crypto_skcipher_type(type);
+ mask = crypto_skcipher_mask(mask);
+
+ for (;;) {
+ alg = crypto_lookup_skcipher(name, type, mask);
+ if (!IS_ERR(alg))
+ return alg;
+
+ err = PTR_ERR(alg);
+ if (err != -EAGAIN)
+ break;
+ if (signal_pending(current)) {
+ err = -EINTR;
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+
+static struct crypto_alg *crypto_user_aead_alg(const char *name, u32 type,
+ u32 mask)
+{
+ int err;
+ struct crypto_alg *alg;
+
+ type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
+ type |= CRYPTO_ALG_TYPE_AEAD;
+ mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
+ mask |= CRYPTO_ALG_TYPE_MASK;
+
+ for (;;) {
+ alg = crypto_lookup_aead(name, type, mask);
+ if (!IS_ERR(alg))
+ return alg;
+
+ err = PTR_ERR(alg);
+ if (err != -EAGAIN)
+ break;
+ if (signal_pending(current)) {
+ err = -EINTR;
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+
+static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct nlattr **attrs)
+{
+ int exact = 0;
+ const char *name;
+ struct crypto_alg *alg;
+ struct crypto_user_alg *p = nlmsg_data(nlh);
+ struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
+
+ if (!netlink_capable(skb, CAP_NET_ADMIN))
+ return -EPERM;
+
+ if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+ return -EINVAL;
+
+ if (strlen(p->cru_driver_name))
+ exact = 1;
+
+ if (priority && !exact)
+ return -EINVAL;
+
+ alg = crypto_alg_match(p, exact);
+ if (alg) {
+ crypto_mod_put(alg);
+ return -EEXIST;
+ }
+
+ if (strlen(p->cru_driver_name))
+ name = p->cru_driver_name;
+ else
+ name = p->cru_name;
+
+ switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
+ case CRYPTO_ALG_TYPE_AEAD:
+ alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
+ break;
+ case CRYPTO_ALG_TYPE_GIVCIPHER:
+ case CRYPTO_ALG_TYPE_BLKCIPHER:
+ case CRYPTO_ALG_TYPE_ABLKCIPHER:
+ alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
+ break;
+ default:
+ alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
+ }
+
+ if (IS_ERR(alg))
+ return PTR_ERR(alg);
+
+ down_write(&crypto_alg_sem);
+
+ if (priority)
+ alg->cra_priority = nla_get_u32(priority);
+
+ up_write(&crypto_alg_sem);
+
+ crypto_mod_put(alg);
+
+ return 0;
+}
+
+#define MSGSIZE(type) sizeof(struct type)
+
+static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
+ [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+ [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+ [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+ [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+};
+
+static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
+ [CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32},
+};
+
+#undef MSGSIZE
+
+static const struct crypto_link {
+ int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
+ int (*dump)(struct sk_buff *, struct netlink_callback *);
+ int (*done)(struct netlink_callback *);
+} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
+ [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
+ [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
+ [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
+ [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report,
+ .dump = crypto_dump_report,
+ .done = crypto_dump_report_done},
+};
+
+static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+ struct nlattr *attrs[CRYPTOCFGA_MAX+1];
+ const struct crypto_link *link;
+ int type, err;
+
+ type = nlh->nlmsg_type;
+ if (type > CRYPTO_MSG_MAX)
+ return -EINVAL;
+
+ type -= CRYPTO_MSG_BASE;
+ link = &crypto_dispatch[type];
+
+ if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
+ (nlh->nlmsg_flags & NLM_F_DUMP))) {
+ struct crypto_alg *alg;
+ u16 dump_alloc = 0;
+
+ if (link->dump == NULL)
+ return -EINVAL;
+
+ list_for_each_entry(alg, &crypto_alg_list, cra_list)
+ dump_alloc += CRYPTO_REPORT_MAXSIZE;
+
+ {
+ struct netlink_dump_control c = {
+ .dump = link->dump,
+ .done = link->done,
+ .min_dump_alloc = dump_alloc,
+ };
+ return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
+ }
+ }
+
+ err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
+ crypto_policy);
+ if (err < 0)
+ return err;
+
+ if (link->doit == NULL)
+ return -EINVAL;
+
+ return link->doit(skb, nlh, attrs);
+}
+
+static void crypto_netlink_rcv(struct sk_buff *skb)
+{
+ mutex_lock(&crypto_cfg_mutex);
+ netlink_rcv_skb(skb, &crypto_user_rcv_msg);
+ mutex_unlock(&crypto_cfg_mutex);
+}
+
+static int __init crypto_user_init(void)
+{
+ struct netlink_kernel_cfg cfg = {
+ .input = crypto_netlink_rcv,
+ };
+
+ crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
+ if (!crypto_nlsk)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void __exit crypto_user_exit(void)
+{
+ netlink_kernel_release(crypto_nlsk);
+}
+
+module_init(crypto_user_init);
+module_exit(crypto_user_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
+MODULE_DESCRIPTION("Crypto userspace configuration API");
+MODULE_ALIAS("net-pf-16-proto-21");
Code Review / kvmfornfv.git / blobdiff